I wouldn't recommend it. My partner is a tattoo artist and I work in the studio - our advice is to avoid swimming for 2 weeks, until the tattoo is completely healed - not only can it affect how the tattoo heals but you're at risk of infection, especially in the first few days after it's been done.
Vaseline is also one of the worst things you can put on a new tattoo, it can draw out the colour and leave it looking patchy.
Best thing to do would be to rearrange the appointment until after the weekend or somehow manage to keep your wrist out of the water!
Hope this helps.